[drp]

Any of you Stax fans know the maximum amp power (if any) the Stax SRD7 Pro can accommodate? I would like to try it with a power amp (B&K EX4200), which I believe is rated for 200wt/ch.

Documentation on this device is scarce to type the least, and I would rather not see the adaptor or my HE60s go poof.

TIA

 

[derekbmn]

The adapter is rated for 30 watts max , but others (and myself) have put MUCH more than that through them. Not so sure how it would hold up on the long term though.

 

[krmathis]

As long as you don't listen to the amplifier at full blast you should be safe.
I have used my SRD-7 Pro/Omega II with the 200w/8ohm Lyngdorf TDAI 2200, and they seem to have taken no damage.

I am pretty sure your ears will take a damage before the energizer.

 

[spritzer]

You can use just about any amp with the adapters but don't crack it to high. The wattage rating isn't just there because the adapter will self destruct but rather the headphones will. Back in the day when Stax sold mostly adapters with the headphones they were fitted with 461v triacs that would short the stators if the voltage would exceed that limit. The limit was there for a reason because the driver is basically doomed if the driver voltage is more the double the bias voltage (this was in the normal bias days) and this can happen still even though we are dealing with a higher bias. Stax stopped using triacs when the amps took over with their fixed maximum output voltage and Sennheiser designed the headphones to be used with their own amps so no protection there either. While it isn't likely that you'll reach 1100v on the stators it can happen if someone flips the wrong switch and then the headphones are toast.

 

[drp]

Thanks for the speedy answer you guys; much appreciated.

This would be for in-bed/late night use so volume levels would remain moderate, since the HE60 is open, but the caveat is well noted.

I'm also curious what the Oppo 970 will do with with SACD through the Baby O.....

 

[spritzer]

For low level listening you shouldn't run into any trouble. It doesn't matter how many watts the amp can produce it will never use more then a portion of them into an SRD7 load.

The Oppo is a good budget player but that's all that it is. The HE60 will make mincemeat of it and show you very flaw mercilessly but that is the price we pay for such stunning resolution.

 

[drp]

Quote:

Originally Posted by spritzer /img/forum/go_quote.gif The Oppo is a good budget player but that's all that it is. The HE60 will make mincemeat of it and show you very flaw mercilessly but that is the price we pay for such stunning resolution.

You bet; the surgical analysis is my goal (plus just for the thrill of it all), and then maybe see what's modifiable (rubs hands together). I bought the Oppo solely as a 720p upscaler for my Plasma screen. Have yet to really try out the SACD, and DVD-A capabilities. I did quickly spin the DVD-A version of Beatles Love Album and was presently surprised how good it sounded on the speaker rig. Might drag my Opus 21 into the fray for an additional analysis of the SRD/power amp combo.

This is also all to see what kind of sound I can get with the SRD 7 in the chain, since I need money and a brand/model decision for an electrostatic amp. Be great to have a power amp fill the bill for a while. Listening to the HE60s through the very simple SRD-7 Pro and Sonic Super T has been a surprisingly positive and gratifying musical experience, but I'm sure not even knocking on potential's door.

ETA - This is my first time into the electrostatic fray. Even with my limited exposure, I can already tell that it is something special; everything is just so smooth and clean non-fatiguing.

Cheers guys!

 

[spritzer]

Sources like the Oppo are great fun to listen to and can often tide us over in a second system. I used the Playstation as a source for a good stretch of time and while it isn't great it has great synergy with the Lambda line, taming the treble brightness and etch.

The Oppo is easily modifiable and so is the SRD-7. By connecting to the transformers directly you will get a good increase in sound quality.

 

[patrickamory]

Quote:

Originally Posted by spritzer /img/forum/go_quote.gif I used the Playstation as a source for a good stretch of time and while it isn't great it has great synergy with the Lambda line, taming the treble brightness and etch.

Ah, very interesting. I wouldn't have pegged you for a PS-1 user. Presumably this was the much talked about SCPH-100X series? I recently got one and am putting it through the obligatory 1-week warm-up period.

I basically can't stand digital audio so I prefer these cheap, warm players for when I have to listen to CD. Currently I'm using the Toshiba 3950 which fills the bill perfectly (haven't had the urge to do the mods, but maybe I will someday for fun).

I've got some extra turntables lying around and piles of cartridges, so if I can figure out how to rearrange the bedroom I'll be hooking one of them up so I can enjoy vinyl on the "modern" head-fi rig as well as the "vintage" one in the living room.

 

[Tachikoma]

Quote:

Originally Posted by spritzer /img/forum/go_quote.gif You can use just about any amp with the adapters but don't crack it to high. The wattage rating isn't just there because the adapter will self destruct but rather the headphones will. Back in the day when Stax sold mostly adapters with the headphones they were fitted with 461v triacs that would short the stators if the voltage would exceed that limit. The limit was there for a reason because the driver is basically doomed if the driver voltage is more the double the bias voltage (this was in the normal bias days) and this can happen still even though we are dealing with a higher bias. Stax stopped using triacs when the amps took over with their fixed maximum output voltage and Sennheiser designed the headphones to be used with their own amps so no protection there either. While it isn't likely that you'll reach 1100v on the stators it can happen if someone flips the wrong switch and then the headphones are toast.

So... going by this, is it possible to overdrive a normal bias headphone using something like a BH? (I am assuming that the BH has a normal bias output)

 

[spritzer]

Quote:

Originally Posted by Tachikoma /img/forum/go_quote.gif So... going by this, is it possible to overdrive a normal bias headphone using something like a BH? (I am assuming that the BH has a normal bias output)

It's very easy actually and the same goes for electret based designs. I use normal phones all the time with my BH but I'm always careful with the volume.

Quote:

Originally Posted by patrickamory /img/forum/go_quote.gif Ah, very interesting. I wouldn't have pegged you for a PS-1 user. Presumably this was the much talked about SCPH-100X series? I recently got one and am putting it through the obligatory 1-week warm-up period. I basically can't stand digital audio so I prefer these cheap, warm players for when I have to listen to CD. Currently I'm using the Toshiba 3950 which fills the bill perfectly (haven't had the urge to do the mods, but maybe I will someday for fun). I've got some extra turntables lying around and piles of cartridges, so if I can figure out how to rearrange the bedroom I'll be hooking one of them up so I can enjoy vinyl on the "modern" head-fi rig as well as the "vintage" one in the living room.

I've had this 1002 machine since it came out so I tried it out. It was ok stock but a Rotel RCD-971 was much more musical and better all round. I modded the crap out of it and hooked it up to a bench supply and then it started to really sing. It started to develop some ground problems after the last round of tinkering so I fixed it and lent it to a friend. It's a good budget source but I'm going to get one of the old TOTL Japanese CDP and rebuild it as a good player for my second system.

In vinyl new I bought a Lenco GL75 last night.

Can't wait to mount it to a new plinth.

 

[patrickamory]

Quote:

Originally Posted by spritzer /img/forum/go_quote.gif In vinyl new I bought a Lenco GL75 last night. Can't wait to mount it to a new plinth.

Awesome! Keep us posted on your progress.

 

[drp]

Perhaps you guys can help with this one as well . . . If you were to use a SRD-7 and a good performing 30 w/ch power amp (pick one in the 2k range), what level of dedicated electrostatic amp would this compare to?

I realize that the logical answer is to buy a good electrostatic amp for the same money, but I may need to buy a new power amp as well.

Can you in fact get scaled up perfomance with a nice power amp? What I'm trying to determine is the point of diminishing return for an amp/srd combination; at what level does the SRD-7 (or any adapter) become a bottleneck?

 

[Michgelsen]

I'm curious as well, because an energizer would enable you to use one of those modern class d amps such as a NuForce. That could be interesting, since they're not that expensive at all.

 

[spritzer]

Quote:

Originally Posted by patrickamory /img/forum/go_quote.gif Awesome! Keep us posted on your progress.

I will

Quote:

Originally Posted by drp /img/forum/go_quote.gif Perhaps you guys can help with this one as well . . . If you were to use a SRD-7 and a good performing 30 w/ch power amp (pick one in the 2k range), what level of dedicated electrostatic amp would this compare to? I realize that the logical answer is to buy a good electrostatic amp for the same money, but I may need to buy a new power amp as well. Can you in fact get scaled up perfomance with a nice power amp? What I'm trying to determine is the point of diminishing return for an amp/srd combination; at what level does the SRD-7 (or any adapter) become a bottleneck?

It's hard to compare the two driving platform like this. The dedicated Stax amps are more detailed and clean sounding while the adapters are more dynamic while sacrificing a lot of detail and resolution.